Carton opening mechanism



CARTON OPENING MECHANISM Filed Aug. 21 1951 I5 Sheets-Sheet 1 INVENTOR CHARLES E. KERR ATTORNEY Oct. 9, 1956 c. E. KERR CARTON OPENING MECHANISM Filed Aug. 21, 1951 s sneaks-sheet 2 INVENTOR CHARLES E.KERR

ATTORNEY Oct. 9, 1956 c. E. KERR 2,765,715

CARTON OPENING MECHANISM Filed Aug. 21, 1951 3 Sheets-Sheet 3 INVENTOR CHARLES E. KERR ATTORNEY CARTON OPENING MECHANISM Charles E. Kerr, Hoopeston, lll., assignor to Food Machinery and Chemical Corporation, San Jose, Calif., a corporation of Delaware Application August 21, 1951, Serial No. 242,951

6 Claims. (Cl. 9353) This invention relates to automatic packaging machinery and is especially concerned with a device operable in connection with cartons for taking the cartons as received in a generally fiat form and erecting them into a hollow rectangular form. A packaging machine utilizing cartons of this character and incorporating features useful with the present device is disclosed in detail in the co-pending application entitled Carton Feeding, Sealing and Filling System, filed December 31, 1948, Serial No. 68,484, by Charles E. Kerr.

In apparatus of this general sort problems are encountered in the event the cartons are not immediately amenable to light pressure for erecting the cartons from their fiat into their hollow condition. In practice it often is necessary to utilize cartons which have some adhesion between the panels. This may be due to numerous causes. There may be residual adhesive utilized in the original manufacture of the carton which escapes from its normal locations and sticks improper parts of the carton together. The erecting mechanism may operate so quickly or may be intended to operate so quickly that atmospheric air has insuficient time to rush between and permit the panels to separate. They consequently bend or crush. More especially, some cartons are made of stock having or finished with a surface coating such as paraflin or the like which has a tendency to cohere when the coated panels do come into contact. There are other reasons why cartons do not invariably and always respond to the erecting mechanism of the machine disclosed in the indicated application.

It is, therefore, an object of the invention to provide a carton opener effective to open previously flat cartons despite the occurrence of one or more of the various difliculties described.

Another object of the invention is to provide an improved carton opener.

A still further object of the invention is to provide a carton opener useful not only in connection with the device of the above mentioned co-pending application but useful generally in carton handling machinery.

A still further object of the invention is to provide a carton opener effective with cartons which have their panels in close juxtaposition.

Another object is to provide carton opening apparatus adapted for use in connection with waxed, or otherwise treated cartons whose side walls are apt to be stuck together when the cartons are in a collapsed condition, and which side walls carry end flaps projecting therefrom similarly apt to be stuck together.

A still further object of the invention is to provide a carton opener effectively operable with high speed packaging machinery.

Other objects together with the foregoing are attained in the embodiment of the invention described in the accompanying description and illustrated in the accompanying drawings in which:

Fig. 1 is a plan view of the carton opening mechanism of the present invention in conjunction with the machine 2,765,715 Patented ct. 9, 1955 fully disclosed in the above mentioned copending application, showing particularly the initial carton feeding mechanism, the carton opener of the present invention, and part of the carton conveying structure.

Fig. 2 is an enlarged cross-section of Fig. 1 taken along line 2-2 thereof, certain parts being broken away to improve the clarity of the disclosure.

Fig. 3 is a perspective, in part diagrammatic and with parts in section and others omitted for improved clarity, showing the carton opener in an early part of its operating cycle.

Fig. 4 is a view similar to Fig. 3 but showing the carton opener in a later part of its cycle.

Fig. 5 is a view similar to Fig. 3 but showing the carton opener in a still later part of its cycle.

Although the carton opener can be embodied in a number of different forms depending upon the particular cartons with which it is to be employed, depending upon the remaining mechanism with which it is utilized and depending also upon other factors, it has been successfully embodied as disclosed herein and particularly in connection with the structure indicated in the above identified pending application.

In this instance the opener is for use with a carton 6. The carton is comprised of several panels including a front panel 7, a back panel 8, and intervening panels or webs 9 and 11 secured to the front and rear panels and normally indistinguishable therefrom except for score or fold lines. Likewise adjoining the panels 7, 8, 9 and 11 at one end are tabs 12, 13, 14 and 15, respectively, which are appropriately contoured and arranged to overlap each other when the carton is erected. Similar tabs 16, 17, 18 and 19 are arranged atthe other end of the carton.

Usually the material of the carton is a fibreboard of some flexibility and in the present instance it is assumed that the carton is made substantially of the configuration and proportions shown in the drawings. The fibreboard is covered with material such as paraflin which tends to cause adhesion or cohesion between juxtaposed panels. As received from the carton factory, the carton panels 7 and 8 are pressed closely together in offset condition as spaced by the intervening webs 9 and 11. Upon occasion, not only are the panels 7, 8, 9 and 11 stuck together but also the tabs 12, 13, 14 and 15 are stuck together. The material of the carton is usually of uniform thickness. At least, the panels 7 and 8 are each of but one thickness of the base material which, with its coating, is held to a closely predetermined dimension. The thickness of the collapsed carton is therefore substantially twice the thickness of the individual panels 7 and 8.

The cartons 6 are received in a group or plurality arranged in a column 21 heid in a carton holder 22 forming part of the general mechanism and supported on the framework 23 thereof. A carton feeder is provided and includes a suitable endless conveyor 24 having feeding fingers 26 thereon effective periodically to dislodge the endmost carton 6 from the column 21 and to displace it edgewise through a feeder guide 27 into a location between guide rollers 28 and 29 suitably disposed on the framework 23.

While in the previously identified device the cartons are preferably fed from a vertical column and in a horizontal direction; that is, with the general plane of the flat, collapsed carton horizontal, in the present instance the cartons are preferably disposed when collapsed and fed with their general plane in a vertical direction.

Pursuant to the present invention, a device is provided for receiving the normally collapsed and sometimes adhered cartons and erecting them into a rectangular hollow configuration suitable for subsequent handling. For this reason, on the framework 23 there is provided at a suitable location a frame 31 in the form of a revolving wheel having a plurality of identical carton holders 32 thereon.

Each carton holder includes a centrally depressed rectangular plate 33 provided with a rubber gasket 33a ter minating in a plane and having an extent somewhat less than the rectangular extent of one of the panels, for example the panel 7. The plate 33 is connected to a hollow spoke 34 included in the wheel and joined through a connection conduit (not shown) with a source of subatmospheric pressure appropriately timed.

The relationship of the rotation of the wheel 31 about its vertical axis on the framework 23 with the operation of the conveyor 24 is such that a carton having been removed from the column 21 and being advanced through the rollers 28 and 29 is at a carefully timed instant brought directly into superposition and registry with the plate 33, so that the plate is appropriately disposed on one side of the front panel 7 in close adjacency thereto. The vacuum is then made effective within the confines of the plate 33 and the weight of the entire carton is then supported by the carton holder 32 on the associated revolving arm 34-, against which the carton is held by atmospheric pressure.

While the panel 7 is so supported and is confined with respect to the wheel 31 or frame the remaining parts of the carton, that is the panel 8, the webs 9 and 11, and the tabs 12, 13, 14 and 15 as well as the tabs 16, 17, 18 and 19 are free with respect to the frame and are held only through the material from which the carton is made.

To assist in the initial positioning of the carton with respect to the frame 31 and to insure that a ciose engagement is provided until the vacuum is effective, the framework 23 is provided with an upright 41 carrying pressure rollers 42 adapted to abut the rear panel and hold it accurately in position, the rollers, however, being arranged to rotate about the axis of the upright 41 with the rotation of the wheel 31 as the arms 34 advance and then to return for a subsequent operation.

As the carton 6 is initially advanced in rotation about the axis of the wheel 31, it is brought away from the pressure rollers 42 and stands freely against the frame 31. At this time mechanism is effective to open the carton despite the fact that panels may be stuck together and despite the fact that the tabs may also be stuck together.

For this purpose, the framework 23 is provided with a central extension 46 coaxial with but extending upwardly through the hub of the wheel 31 and carrying and providing a stationary bos 47. Appropriately supported on the various arms 34 and included in the frame 31 for rotation about the axis thereof is a drum 48 provided with a number of identical rocking levers 49.

Each rocking lever 49 is arranged generally radially of the drum 48 and at one end is provided with a pivot connection 51 to a lug '2 upstanding from the frame 31. The motion of the rocking lever 49 about the pivot 51 is controlled by a cam disc 53 secured on the stationary boss 47 of the framework and providing a surface 54 which is in part planar and perpendicular to the axi of the boss 47, is in part inclined downwardly toward a depression 56 and is in part inclined upwardly from the depression back to the planar surface.

Designed to cooperate with the cam disc is a cam follower 5'7 including a tappet 58 confined to translation within the drum 4 -3 and at its lower end carrying an anti-friction roller 59 in immediate contact with the cam disc. The follower 57 likewise includes two links 61 connected by a pivot 62 to the plunger 58 and by a pivot 63 to the rocking lever 49. As the frame 31 or Wheel rotates about the stationary framework 23 and about the stationary cam disc 53, the follower 57 is effective to move the rocking lever 49 in an angular sweep in a vertical plane.

To insure that the follower remains in contact with the cam disc even during high speed operation, the pivot 63 is provided with an extension 66 to which one end of a tension spring 67 is attached. A pin 68 projecting from the drum 43 serves as an anchor for the other end of the spring 67. in this fashion, the rocking lever 49 is made to oscillate in appropriately timed or cyclic fashion with respect to the rotation of the wheei 31.

Advantage is taken of the motion of the rocking lever 49 to operate a plunger '71.. The plunger is in the nature of an elongated plate between its ends pierced to afford a bearing for a pivot pin 72 passing through a fork end '73 of the rocking lever 49 so that the plunger 71 is provided with a straddle mounted articulation. The upper, extended end of the plunger is formed with a pair of fastening openings 74 and 76 for the alternative reception of one hooked end 77 of a tension spring 78, the other end of which engages a bolt 79 projecting from the body of t re rocking lever 49.

The plunger 71 along its inner edge 81 is of a generally rectilinear contour or more particularly is straight and nearly vertical in most positions of the structure.

Means are provided for guiding the movement of the plunger 71 in addition to the guidance afforded by the pivot pin 72 on the rocking lever 49. For this reason, the drum 4-5 included in the frame 31 is appropriately provided with a plate 32. in this plate there is provided an elongated opening 33 through which a pair of fasteners 84 and 86 pass into a subjacent flange 87 projecting from the drum 4%. By this mechanism, the radial location of the plate 82 with respect to the remainder of the frame 31 is variably established.

Also piercing the plate 82 is an aperture 88 of generally rectangular configuration slightly larger than the largest cross-sectional contour of the plunger 71 and leaving in the plate 82 a portion 89 whose inner edge functions as a guide for the plunger 71.

Designed to extend into the aperture 38 and to bear against the plunger-guiding edge of the portion 89 is a cam 91 formed as part of the plunger 71 on the edge thereof opposite to the straight inner edge 81. The cam 91 is provided with an inclined surface 92 at its lower end which, when considered with the straight edge 81, provides a wedge on the leading, depending portion of the plunger 71. The inclined surface 92 is slanted and disposed to provide a radially inward component of motion of the lower part of the plunger as the plunger descends with respect to the guide 89.

Immediately adjacent the inclined surface 92 and included in the cam 91 is a relatively straight dwell portion 93 approximately parallel to the straight edge 81 and merging with an arcuately concave contour 94 occupying substantially the remaining portion of the radially outer cam edge of the plunger. The inclinations of the portions 92, 93, and 94 are such that as they are held in contact with the guide 89 by the spring 78 during the descent of the plunger 71 under the influence of the rocking lever 49, the plunger itself and particularly the point 96 thereof is made to traverse a predetermined path.

The travel of the descending plunger is confined laterally, understood to be generally in a circumferential direction with respect to the wheel or frame 31, by the sides of the guide plate 82 at either side of the opening 88 and by the rocking lever 49 which itself is confined against such lateral motion by the pivot pin 51 and in turn confines the plunger by the pivot pin 72. The transverse movement of the plunger, understood to be generally the radially inward and outward movement of the plunger with respect to the wheel or frame 31, is defined in part by the pivot connection 72 and in part and largely by the interface contact between the plunger cam side and the guide 39.

Preferably the inclination 92 and the remaining parts of the cam are such that as the plunger descends the cam point 96 follows a path approximately as indicated by the broken line 97 in Fig. 2 and which has a transverse (radial) component downwardly and inwardly with respect to the frame. The path 97 actually is, such that the plunger collides with the inner upstanding tab 12 of the carton. The configuration of the outer tab 13 is such that the laterally central portion of the tab 12 is exposed for contact by the plunger 71 in its transverse movement.

If such is not normally the case, the carton 6 can be provided with a cut out portion 98 or notch in the outermost tab to expose the inner tab 12 for immediate contact with the plunger 71. The purpose of this is to permit the plunger 71 to move downwardly into immediate abutment with the inner tab 12 and to displace it transversely or radially inwardly to bend the inner tab 12 about its fold line with respect to the remaining part of the carton and especially with respect to the stationarily held inner panel 7 thereof. This motion inwardly and downwardly of the plunger 71 separates the upper tabs 12 and 13 should they be stuck together previously, and in any event locates the plunger 71 on the inside or interior surface of the inner panel 7.

Once the upper tab 12 has been bent by contact with the plunger 71, the path 97 of the point 96 of the plunger then continues downwardly but is radially outward in the transverse direction so that the point 96, about the time that the plunger leaves the upper tab 12 and begins to traverse the laterally central part of the panel 7, is disposed at a predetermined distance away from the subjacent carton holder 32. The space existing between the point 96 or the adjacent straight side 81 of the plunger and the carton holder is only slightly more than or is just over the predetermined thickness of the carton panel 7. This means that the plunger in its further descending movement does not scuff or score or deface the finish on the interior of the carton panel 7 but is spaced very slightly therefrom as determined by the interengagement of the cam surfaces 92, 93 and 94 with the follower 89.

The width of the plunger 71 increases from the point 96 along the inclined surface 92 to a value much greater than the infinitesimal space, if any, previously provided between the panels 7 and 8. Consequently, in its descending movement the plunger dislodges the outer panel 8 from the inner panel 7 and breaks any possible adhesion or cohesion therebetween and between the flaps 13 and 14, as well as between the flaps 12 and 15. The normal stiffness of the material of the carton is such that it is not always necessary for the plunger 71 to descend for the full height of the carton. A partial penetration between the panels 7 and 8 is usually sufficient to separate them substantially and to separate the lower tabs 16, 17, 18 and 19. Panel separation is accompanied by an effective rotation of the side webs 9 and 11 with respect to the front and back panels and results in a partial erection of the carton.

During the time that the plunger '71 is descending in a predetermined path traversing the carton holder 32, (a curvilinear path initially which terminates in a substantially rectilinear path with the latter part of the downward movement) the frame 31 or wheel is rotating so that when the roller 59 finally is in the depression 56 of the cam disc, the plunger 71 has descended as far as possible and the car-ton is not only unstuck but is partially erected.

At about this time in the rotation of the wheel, one of a plurality of erecting arms 1111 is made effective. The erecting arms are described in detail in the mentioned copending application. In general each of them is moved by a cam follower 1132 held against a cam plate 103 on the framework 23 by a pressure spring 104. The shape of the cam plate 1% is such, as particularly illustrated in Fig. 1, that during the initial part of a. cycle of a carton holder and as its carton is being partially erected during the descent of the plunger 71, the associated erecting arm 101 lags behind and stays out of contact with the carton.

Substantially at the time the plunger has made its maximum descent and the carton is partially erected, the cam plate 103 is effective to revolve the erecting arm 101,

against the urgency of the spring 104, to engage with or near the inclined web 9 of [the carton. This engagement is such as to afford an additional point of support for the carton over and above that afforded by the carton holder 32 and hence the carton is held in at least partially erected form. Preferably, the contour of the cam plate 103 is such that the erection arm 101 continues its rotary movement and erects the carton from a partially open position through open position and to an overstressed position.

After the erecting arm has collided with and has taken over the further opening motion of the carton, the follower 59 rides up the ramp of the cam disc 53 and rocks the lever 49 in the reverse direction so the plunger 71 is withdrawn from between the spaced apart walls of the carton. The return path of the plunger 71 is identical, substantially, with its initial path since the spring 78 still causes the cam surfaces 92, 93 and 94 to bear against the cam follower 89. Eventually the plunger 71 is entirely withdrawn into a position disposed substantially above the uppermost part of the erected carton which is then transferred to a conveyor mechanism 106 similar to that described in detail in the above mentioned copcnding application.

The entire operation of driving the plunger 71 between the juxtaposed panels of the carton and withdrawing it occupies something less than a degree rotation of the frame 31 on the framework 23. During the remaining portion of the rotation of the wheel 31, the levers 49 remain in their uppermost position and the plungers 71 remain withdrawn ready for subsequent descent as they come into the initial position. The cycle repeats indefinitely as the cartons are fed from the column 21 into the machine. The carton opener, being appropriately interposed between the feeding mechanism and the subsequent conveyor 1%, in every instance makes the cartons open even though their juxtaposed panels may have been stuck together. The opener holds the panels in partially open position until they are finally completely erected by the erecting arms during the withdrawal of the opener plunger.

Having thus described my invention what I claim as new and desire to protect by Letters Patent is as follows:

1. A device for opening a carton that is collapsed with opposed side panels disposed closely adjacent each other and an end flap extending from each side panel, said device comprising means for gripping the exterior surface of one side panel to support said carton with all portions in unsupported condition except said one side panel, a plunger mounted adjacent said carton supporting means and having a wedge-shaped forward end portion, means for moving said plunger end portion in an oblique direction toward said carton and into contact with the inner surface of one of said end flaps to simultaneously bend said flap away from the opposed flap and position said plunger between said flaps, then moving said plunger end in a direction inwardly of said carton to progressively separate said side panels, and then moving said plunger away from the gripping means to further separate the side panels.

2. A device for opening a collapsed carton that has opposed side panels disposed closely adjacent each other and an end flapextending from each side panel, said device comprising means for gripping one side panel of said carton to support the carton in an upright position with the end flaps projecting above the side panels, a plunger mounted adjacent said carton supporting means, means for moving said plunger downwardly toward and into the carton, means for initially guiding the plunger during descent thereof in an oblique path to direct the plunger into contact with the end flap on said supported side panel and bend it away from the opposed end flap and for guiding said plunger in an oblique path away from said supported side panel and into contact with the side panel opposite thereto.

3. A carton opener comprising a frame, a canton support on said frame, an actuating lever pivotally mounted on said frame, means for pivoting said lever, a plunger pivotally mounted on said lever for actuation as said lever is pivoted, guide means mounted in fixed position on said frame, a cam surface on said plunger in contact witi said guide means, said guide means being arranged to direct said plunger along a predetermined path successively in oppositely inclined directions as said plunger is actuated by said lever, and spring means connected. between said plunger and said lever for pressing said cam surface against said guide means.

4. A device for opening a carton that is in collapsed condition with opposed side panels closely adjacent each other and an end flap extending from each side panel, said device comprising a frame, a support member mounted in fixed position on said frame and arranged to grip one side panel of the carton to support the carton in fined posi tion relative to the frame, a rocking lever pivotally mounted on said frame directly above said carton support 5 member, a plunger pivotally connected to said lever and extending downwardly therefrom, guide means disposed on said frame at a point above the carton on said support means and spaced from the plane of the carton, said plunger having a cam surface in contact with said guide means during the downward movement of said plunger, said cam surface having a contour efiective to cause an initial oblique movement of the plunger toward the inner surface of one of said carton end flaps and into contact therewith to bend said flap away from the opposed flap, and a subsequent substantially vertical movement of the plunger downwardly between the side panels of said carton.

5. A device for opening a carton that is in collapsed condition with opposed side panels closely adjacent each other and an end flap extending from each side panel, said device comprising a frame, means for supporting the carton in predeterm ned position relative to the frame, an actuating member movably mounted on said frame in alignment with a carton supported by said supporting means, a plunger operably connected to said actuating means and extending therefrom toward the carton, guide means on said frame, said plunger having a cam surface in contact with said guide means during the movement of said plunger, said cam surface having a contour effective to cause an initial oblique movement of the plunger toward the inner surface of one of said carton end flaps and into contact therewith :to bend said flap away from the opposed flap, and a subsequent substantially vertical movement of the plunger between the side panels of said carton.

6. Apparatus for erecting a collapsed carton having opposed side panels closely adjacent each other and end flaps extending from the side panels, comprising a recip ocally mounted actuating member, a plunger extending from the actuating member substantially in the direction of reciprocation thereof and pivoted thereto for rocking motion transversely of said direction of reciprocation, means for reciprocating the actuating member, means for supporting a collapsed carton substantially in the path of the piunger with an end of the carton directed toward th, plunger and with the general plane of the collapsed carton substantially perpendicular to the direction of said rocking motion, a guide slidably engageaole by the plunger during reciprocation thereof, said plunger having a relativeiy thin leading end and a camrning surface including an oblique portion extending from the leading end to a relatively thicker intermediate portion of the plunger, 21 dwell portion defining said thicker portion of the plunger and a concave portion extending from the dwell portion, and means yieldably urging the plunger about the axis of its pivotal connection to the actuating means to hold said camrning surface of the plunger slidably against the guide and thereby predetermine the path of the leading end of the plunger during reciprocation thereof.

References Cited in the file of this patent UNITED STATES PATENTS 1,081,268 Heybach Aug. 22, 1911 1,313,975 Anderson Aug. 26, 1919 1,527,030 Delamere et al. Feb. 17, 1925 1,779,817 Lane Oct. 28, 1930 2,016,814 Ferguson Oct. 8, 1935 2,318,208 First May 4-, 1943 2,598,071 Rose et al May 27, 1952 

